Compact laser device and method for hair removal

Abstract

A device for hair removal includes the use of infrared laser having wavelength of about 0.7 to 1.1 microns, energy per pulse of about 0.5 to 5.0 J on the skin surface and operated at about 1.0 to 5.0 Hz. The treated area includes one or more than one of the following: the hair shaft, root, hair follicle, papilla, blood vessels feeding the papilla, or blood vessels in the papilla. The delivery means includes an optical fiber or fiber bundle which delivers said laser beam to said treated skin, where the optical fibers is further connected to a hand piece containing the laser unit and optics. The laser beam is generated from a laser unit consisting of about 1 to 5 diode arrays having the same wavelength at about 0.7 to 1.1 microns, or a combination of 2 to 3 different wavelengths selected from the ranges of about 700 to 760 nm, 780 to 820 nm, 900 to 930 nm, or 970 to 990 nm.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to laser device and method for hair removal. More particularly, it relates to systems of using a compact diode laser device at low power with multiple wavelength output for all skin type and hair color. [0003] 2. Prior Art [0004] Different lasers have been disclosed for hair removal since the first low energy normal mode ruby (at 694 nm) and Nd:YAG (at 1064 nm) lasers were disclosed in 1967, U.S. Pat. No. 3,538,919. These prior arts include the earlier approaches using a pulsed, or Q-switched ruby laser disclosed in 1990 by Zaim in U.S. Pat. No. 5,059,192; high energy normal mode ruby laser disclosed in 1997 by Anderson et. al. in U.S. Pat. No. 5,595,568; and the more recent patents of Anderson et. al. (U.S. Pat. Nos. 5,735,884, 6,183,773), Tankovick (U.S. Pat. No. 5,752,948). Alexandrite laser (at 755 nm) was proposed in U.S. Pat. No. 5,879,346 (of Waldman et al); U.S. Pat. Nos. 5,871,...

AI Technical Summary

Benefits of technology

[0009] It is yet another preferred embodiment of this invention includes a handheld design where the optical or electrical parts of the device may be integrated into a compact size for convenient use similar to a razor.

[0010] It is yet another preferred embodiment of this invention includes formulas for lens design including parameters for optimal focal length, laser spot size and maximal penetration depth for best clinical outcome.

[0013] It is yet another preferred embodiment of this invention includes a method and device to combine multiple wavelength laser source having a wavelength range of 700 to 1100 nm, where at least two different wavelength laser can be integrated into one unit. The preferred laser source includes semiconductor diode-laser, most preferable at about 750, 810, 920 and 980 nm, or combination of at least two of these preferred spectra. The multiple wavelength device for hair removal is more efficient for all skin types and hair color, where various portions of the hair and surrounding tissues or blood vessels at different depth (3 to 10 mm) can be efficiently damaged.

Problems solved by technology

The proposed non-specified laser, however, is not yet technically available, except a low power diode laser which can not be frequency doubled to 450 to 470 nm.

Therefore, the method proposed in this prior art is not technically practical, and no systems have been made based on this method.

In addition, they all use a single fixed wavelength and non-focused laser which limits the laser penetration to a fixed depth and therefore it is not optimized for different skin types or hair color, although pulse duration of 5 to 400 microseconds was adjustable in these commercial systems.

These high energy, high power systems also suffer from the risk of burning or damaging the skin epidermis, even step of cooling is included.

Furthermore, the existing systems generally require 3 to 4 treatments because they can not produce sufficient temperature in those hair follicles which do not contain a hair shaft or have a deep roots (deeper than 5 mm).

Furthermore, there is a need of compact size, low-power laser device for personal or family uses, rather than the high-power, high-cost and bulky system which is limited for clinical or hospital use.

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